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    <script>
      function timeoutPromise(delay){
        return new Promise((resolve, reject) => {
          setTimeout(() => {
            //   console.log(1)
            resolve(`延迟了${delay}秒钟`)
          }, delay*1000 )
        })
      }
        const p = timeoutPromise(1)
          .then((res) => {
            console.log(res) // 打印1
            return timeoutPromise(2)
          })
          .then((res) => {
            console.log(res)
            return timeoutPromise(3)
          })
          .then((res) => {
            console.log(res)
          })
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